Ping

Today, other methods of checking connection speed and quality exist, such as traceroute or pinging other large sites such as google.com or cnn.com, but due to the meme Yahoo has remained popular. The images on these cards are generally based on colored photographs, and are readily identified by the glossy appearance given by the paper's coating. It caught on, because in early 1990s, Yahoo was the primary hub of useful information and the domain name was already well known, and had a high uptime due to its then-unique use of Akamai load balancing. The last and current postcard era, which began about 1939, is the "photochrome" or "chrome" era. Many Internet Service Provider support technicians and simply tech-savvy individuals recommended pinging yahoo.com, creating this meme. The "linen card" era lasted from about 1930 to 1945, when cards were primarily printed on papers with a high rag content. In the early 1990s, many people began to ping yahoo.com when their internet connection seemed slow or dead. The "white border" era, named for obvious reasons, lasted from about 1916 to 1930.

The Windows ping utility returns the same information as the Unix implementations, albeit with different formatting. Thus began the Golden Age of American postcards, which lasted until about 1915, when World War I blocked the import of the fine German-printed cards. On a system with a BSD Unix lineage, ping traditionally only answers whether a host is ”alive” or not, but modern systems may provide a more System V–like output as shown above. The "divided back" card, with space for a message on the address side, came into use in the United States in 1907. The above sample is typical of ping on an operating system with a UNIX System V lineage. This "undivided back" is what gives this postcard era its name. Below is a sample output where the wikipedia.com server is "pinged":. Written messages were still restricted to the front side, with the entire back dedicated to the address.

The output of ping, and its cousins, generally consists of the packet size used, the host queried, the ICMP sequence number, the time to live, and the round-trip delay time, with all times given in milliseconds, and times below 10 milliseconds often having low accuracy. 1901 brought cards with the word "Post Card" printed on the reverse (the side without the picture). The syntax is "ping -x <input>". A correspondent's writing was allowed only on the front side of these cards. The following switches are available to expand Ping's usefulness. Shortly thereafter the United States government, via the United States Postal Service, allowed printers to publish a 1-cent postcard (the "Penny Postcard"). The syntax is "ping -x <input>". The first postcard in the United States was created in 1893 to advertise the World's Columbian Exposition in Chicago, Illinois.

The following switches are available to expand Ping's usefulness. The idea is that it stands out and cannot be filed away in a folder somewhere. Internet worms such as Welchia flooded the Internet with ping requests as they sought to locate new hosts to infect, causing problems to routers across the Internet. Some activists create oversized postcards on poster boards urging action on a particular issue and mail them to public officials' offices. The usefulness of ping in assisting the "diagnosis" of Internet connectivity issues was impaired from late in 2003, when a number of Internet Service Providers filtered out ICMP Type 8 (echo request) messages at their network boundaries. The study and collecting of postcards is termed deltiology. Mills provided a backronym, "Packet Internet Grouper (Groper)", also by other people "Packed Internet Gopher", after the small rodents ). The art form is called mail art.

(Later David L. In the art world the postcard can also be translated into an art object. He named it after the pulses of sound made by a sonar, since its operation is analogous to active sonar in submarines, in which an operator issues a pulse of energy (a network packet) at the target, which then bounces from the target and is received by the operator. While a postcard is usually printed by a private company, individual or organization, a postal card is issued by the relevant postal authority. Mike Muuss wrote the program in December, 1983, as a tool to troubleshoot odd behavior on an IP network. It is distinguished by stamp collectors from a postal card in that the postage is pre-printed on the latter, whereas a postcard requires a stamp. . A postcard or post card is a typically rectangular piece of thick paper or thin cardboard intended for writing and mailing without an envelope and at a lower rate than a letter.

It works by sending ICMP “echo request” packets to the target host and listening for replies (ICMP “echo response” packets). Ping provides estimates of the round-trip time and packet loss rate between hosts. It provides a basic test of whether a particular host is operating properly and is reachable on the network from the testing host. Ping is the name of a computer network tool used on TCP/IP networks (such as the Internet).

-W <timeout> - Time to wait for a response, in seconds. -w <deadline> - Specify a timeout, in seconds, before ping exits regardless of how many packets have been sent or received. -V - Show version and exit. -v - Verbose output.

-U - Print full user-to-user latency (the old behaviour). -M <hint> - Select Path MTU Discovery strategy. -T <timestamp option> - Set special IP timestamp options. -t <ttl> - Set the IP Time to Live.

-S <sndbuf> - Set socket sndbuf. -s <packetsize> - Specifies the number of data bytes to be sent. -r - Bypass the normal routing tables and send directly to a host on an attached interface. -R - Record route.

-q - Quiet output. -Q <tos> - Set Quality of Service -related bits in ICMP datagrams. -p <pattern> - You may specify up to 16 pad bytes to fill out the packet you send. -n - Numeric output only.

-L - Suppress loopback of multicast packets. -l <preload> - If preload is specified, ping sends that many packets not waiting for reply. -I <interface address> - Set source address to specified interface address. -i <interval> - Wait interval seconds between sending each packet.

-f - Flood ping. -F <flow label> - Allocate and set 20 bit flow label on echo request packets. -d - Set the SO_DEBUG option on the socket being used. -c <count> - Stop after sending count ECHO_REQUEST packets.

-B - Do not allow ping to change source address of probes. -b - Allow pinging a broadcast address. -A - Adaptive ping. -a - Audible ping.

-w <timeout> - Timeout in milliseconds to wait for each reply. -k <host-list> - Strict source route along host-list. -j <host-list> - Loose source route along host-list. -s <count> - Timestamp for count hops.

-r <count> - Record route for count hops. -v <TOS> - Type Of Service. -i <TTL> - Time To Live. -f - Set Don't Fragment flag in packet.

-l <size> - Send buffer size. -n <count> - Number of echo requests to send. -a - Resolve addresses to hostnames. -t - Ping the specifed host until interrupted.